Hover support

internal/lsp/requests.go

@@ -3,7 +3,8 @@ package lsp
 import (
 	"encoding/json"
 
-	"github.com/sourcegraph/go-lsp"
+	lsp "go.lsp.dev/protocol"
+	"go.lsp.dev/uri"
 )
 
 type RPCCompletion struct {
@@ -12,6 +13,19 @@ type RPCCompletion struct {
 	Result     lsp.CompletionList `json:"result"`
 }
 
+type RPCHover struct {
+	RPCVersion string    `json:"jsonrpc"`
+	ID         int       `json:"id"`
+	Result     lsp.Hover `json:"result"`
+}
+
+func Position(x, y int) lsp.Position {
+	return lsp.Position{
+		Line:      float64(y),
+		Character: float64(x),
+	}
+}
+
 func (s *Server) DocumentFormat() {
 
 }
@@ -22,19 +36,19 @@ func (s *Server) DocumentRangeFormat() {
 
 func (s *Server) Completion(filename string, pos lsp.Position) ([]lsp.CompletionItem, error) {
 	cc := lsp.CompletionContext{
-		TriggerKind: lsp.CTKInvoked,
+		TriggerKind: lsp.Invoked,
 	}
 
 	docpos := lsp.TextDocumentPositionParams{
 		TextDocument: lsp.TextDocumentIdentifier{
-			URI: lsp.DocumentURI("file://" + filename),
+			URI: uri.File(filename),
 		},
 		Position: pos,
 	}
 
 	params := lsp.CompletionParams{
 		TextDocumentPositionParams: docpos,
-		Context:                    cc,
+		Context:                    &cc,
 	}
 	resp, err := s.sendRequest("textDocument/completion", params)
 	if err != nil {
@@ -53,3 +67,25 @@ func (s *Server) Completion(filename string, pos lsp.Position) ([]lsp.Completion
 func (s *Server) CompletionResolve() {
 
 }
+
+func (s *Server) Hover(filename string, pos lsp.Position) (string, error) {
+	params := lsp.TextDocumentPositionParams{
+		TextDocument: lsp.TextDocumentIdentifier{
+			URI: uri.File(filename),
+		},
+		Position: pos,
+	}
+
+	resp, err := s.sendRequest("textDocument/hover", params)
+	if err != nil {
+		return "", err
+	}
+
+	var r RPCHover
+	err = json.Unmarshal(resp, &r)
+	if err != nil {
+		return "", err
+	}
+
+	return r.Result.Contents.Value, nil
+}